Rotary machines of the sliding vane type having interconnected vane slots

ABSTRACT

Improvement in rotary machines of the sliding-vane type, which have a stator housing, a rotor operatively mounted therein with vane slots to accommodate sliding vanes, is disclosed and comprises a series of channels provided on or in the rotor body and interconnecting the vane slots.

United States Patent 11 1 Kalen et al. 1 5] Oct. 28, 1975 [54] ROTARY MACHINES OF THE SLIDING 706,158 8/1902 Charles 418/268 V N]; T PE HAVING INTERCONNECTED 869,050 10/1907 Blackmer 418/269 1,144,258 6/1915 Smith 418/77 VANE SLOTS 2,423,271 7/1947 Talbot 418/269 [75] Inventors: Hans Kalen, Kolmarden; Kurt 2,520,724 8/1950 Jessop 418/269 Pettersson, Norrkoping, both of Sweden FOREIGN PATENTS OR APPLICATIONS 151,856 10/1920 United Kingdom 418/269 [73] Asslgnee. gtalliRefrigeratlon AB, Norrkoplng, 171,677 Q1906 Germany u we 317,845- 5/1934 Italy 418/269 22 Filed: on. 11, 1973 1 21 L 405 314 Primary Examiner-John .1. Vrablik Attorney, Agent, or Firm-Eric Y. Munson [30] Foreign Application Priority Data Oct. 17, 1972 Sweden 13343/72 52 us. c1. 418/77; 418/238; 418/269 ABSTRACT 2 [51] Int. Cl. ..F01C l/00, Improvement in rotary machines of the Sliding vane [58] Field of Search 418/77 236 238 253 type, which have a stator housing, a rotor operatively /2 mounted therein with vane slots to accommodate sliding vanes, is disclosed and comprises a series of chan- [56] References Cited nels provided on or in the rotor body and intercon- UNITED STATES PATENTS 2/1889 Huson 418/268 necting the vane slots.

3 Claims, 5 Drawing Figures US. Patent Oct.28,1975 3,915,598

ROTARY MACHINES OF THE SLIDING VANE TYPE HAVING INTERCONNECTED VANE SLOTS BACKGROUND OF THE INVENTION In the operation of conventional sliding-vane rotary machines typically compressors, the vanes slide in their respective rotor slots toward the inner surface of the stator and sequentially make contact therewith. During the rotary cycle, the sliding vanes are subjected to strongly varying forces such as gas pressure, centrifugal force, friction and acceleration. These forces may influence the sliding movement of the vanes to such an extent that they are retracted from, and then thrust outwardly against the inner surface of the stator with con siderable force.

This behavior, known as vane hopping, creates a knocking sound, causes denting and corrugation of the stator surface, and results in rapid and excessive wear of both the stator and the contacting vanes.

SUMMARY OF THE INVENTION It is the primary object of this invention to provide a novel and effective means for preventing the vane hopping in sliding-vane rotary machines described above.

While other methods of reducing the sliding vane movements have been employed, the present invention achieves most satisfactory results in modulating excessive vane contact with the stator surface and eliminating rapid wear. In accordance with the concepts herein disclosed, suitably oriented and dimensioned channels are provided on or in the rotor body between adjacent vane slots, thus interconnecting the spaces in these slots which occur cyclically below the vanes. A flow of gas between the vane slots results, moderating the movement of the sliding vanes and creating smooth satisfactory contact between the tops of the vanes and the stator surface during the entire operating cycle.

The present invention will be further described with reference to the accompanying illustrative drawings, and defined by the accompanying claims.

DRAWINGS DESCRIPTION The sliding-vane compressor of FIG. 1 has rotor 1 provided with vane slots 2 and vanes 3, as well as surrounding stator 4 with inlet opening 5 and outlet channel 6. The rotor shaft is conventionally journalled in stator end sections (not shown) which also serve to enclose the compressor unit.

As clearly shown in FIGS. 1, 2 and 3, channel grooves 7 are formed on one or both surfaces of rotor body 1, each connecting the inner bottom of a vane slot 2 with its adjacent vane slot 2. In FIG. 1, the arrows shown on vanes 3 show the direction of movement of vanes 3 during rotation of the compressor, while the arrows in vane slots 2 and channels 7 indicate the corresponding gas flow therein. Suitable positioning and dimensioning of channel grooves 7, as shown, produces a throttling of gas pressure below vanes 3 which balances the pressure influencing vanes 3 in the opposite direction; at the same time, a gas flow occurs which prevents the gas pressure below outwardly moving vanes 3 from falling too low to effectuate full vane operation.

The alternate embodiment of FIG. 4 has channel passages 8 formed within rotor body 1, replacing the surface channels of FIGS. 1-3 and serving exactly the same purpose.

The embodiment shown in FIG. 5 has channels 9 so located that the closing off of channels 9 by inwardly moving vanes 3 at a suitable moment of the operation cycle is ensured. During the continued inward movement of vanes 3, the gas enclosed is compressed and thus acquires the counter-pressure necessary for satisfactory vane function.

What is claimed is:

1. A rotary machine of the sliding vane type, comprising:

a. a stator having an inner cylindrical surface;

b. a rotor eccentrically housed within said stator defining therebetween a working chamber having inlet and outlet passage means for a compressed fluid working medium;

c. a plurality of vane slots in said rotor extending from the central portion of said rotor outwardly to the peripheral surface thereof and being closed at their inner ends;

d. a vane mounted in each of said slots to move therein in an outward and inward direction in response to the increasing and decreasing volume of the working chamber to provide yieldingly sliding contact with the inner surface of the stator during the operating cycles of the rotor;

e. narrowed channels interconnecting said slots to provide restricted flow communication for the working medium from the inner closed end of the slots to a location on an adjacent slot spaced outwardly from the inner closed end thereof;

f. said channels being located so as to provide flow communication between two adjacent slots only during a predetermined movement of the vanes therein whereafter the vane by its inward movement interrupts flow through said channels and prevents communication between said two adjacent slots.

2. A rotary machine according to claim 1, in which said channels extend from the bottom of one vane slot to an adjacent vane slot at a location having a radius greater than that corresponding to the bottom position of the innermost edge of the vane operating in said adjacent vane slot, and at a radius less than that corresponding to the outermost position of the innermost edge of the same vane.

3. A rotary machine according to claim 1, in which said channels are effective to reduce fluid pressure beneath the inwardly moving vanes in response to the increased pressure exerted by the decreasing volume of the working chamber and to increase the pressure he neath the outwardly moving vanes in response to the increasing volume of the working chamber during the operating cycles of the rotor. 

1. A rotary machine of the sliding vane type, comprising: a. a stator having an inner cylindrical surface; b. a rotor eccentrically housed within said stator defining therebetween a working chamber having inlet and outlet passage means for a compressed fluid working medium; c. a plurality of vane slots in said rotor extending from the central portion of said rotor outwardly to the peripheral surface thereof and being closed at their inner ends; d. a vane mounted in each of said slots to move therein in an outward and inward direction in response to the increasing and decreasing volume of the working chamber to provide yieldingly sliding contact with the inner surface of the stator during the operating cycles of the rotor; e. narrowed channels interconnecting said slots to provide restricted flow communication for the working medium from the inner closed end of the slots to a location on an adjacent slot spaced outwardly from the inner closed end thereof; f. said channels being located so as to provide flow communication between two adjacent slots only during a predetermined movement of the vanes therein whereafter the vane by its inward movement interrupts flow through said channels and prevents communication between said two adjacent slots.
 2. A rotary machine according to claim 1, in which said channels extend from the bottom of one vane slot to an adjacent vane slot at a location having a radius greater than that corresponding to the bottom position of the innermost edge of the vane operating in said adjacent vane slot, and at a radius less than that corresponding to the outermost position of the innermost edge of the same vane.
 3. A rotary machine according to claim 1, in which said channels are effective to reduce fluid pressure beneath the inwardly moving vanes in response to the increased pressure exerted by the decreasing volume of the working chamber and to increase the pressure beneath the outwardly moving vanes in response to the increasing volume of the working chamber during the operating cycles of the rotor. 